Always wondering why you get red eyes from smoking weed? Me too! In this article we dive into the red-eye effect, how long it takes and how to get rid of it. Don’t worry, it is a completely harmless side effect of cannabis.
Why do you get red eyes from smoking weed?
How long does your eyes stay red from weed?
How to prevent red eyes after smoking cannabis?
Does everybody get red eyes from using marihuana?
Is there any harm in getting red eyes?
Will eating cannabis help compared to smoking?
Why do you get red eyes from smoking weed?
Most of us have experienced the red-eye effect by themselves or saw it at one oy their friends. The white part of your eye can turn a bit more red when being high. Those red eyes, which are also known as conjunctival hyperemia, are caused by the dilation of the blood vessels in your eye (1). This happens because weed contains both THC and CBD which can widen your blood vessels.
When THC enters the bloodstream, it interacts with cannabinoid receptors throughout the body, including those in the eyes. This interaction ultimately leads to the dilation of blood vessels in the white part of your eye.
CBD, the non-psychoactive cannabinoid in weed, doesn’t give you the ‘high’ feeling like THC, but it can also contribute to red eyes. This is because CBD also interacts with the cannabinoid receptors, however the effect on the blood vessels in your eyes is less strong than with THC.
Next to that, using cannabis can result in decreased tear production, which leads to dry and red eyes. Personally we always have a bottle of eyedrops in our stash box to be used as artificial tears to hydrate the eyes.
How long does your eyes stay red from weed?
How long it takes does depend on the way you consumed cannabis. The effects, and red eyes, from smoking weed are typically shorter than eating edibles.
The redness in your eyes caused by smoking weed will typically fade away within 2-4 hours. Especially the first hour the blood vessels will be the most dilated. The red eyes after eating edibles can take longer and can last anywhere from 4-8 hours.
There are some factors which can affect how long it takes till your eyes are as white as normal. The most important factor is the dosage of THC and CBD. The more you consume, the longer your eyes will stay red (2). Your tolerance and sensitivity to weed also plays a role.
So if you are reading this while being high, don’t worry, your eyes will eventually get back to normal. Of course we also have some tips to speed up this process.
How to get rid of red eyes?
Even though we think enjoying cannabis should be destigmatized, in some situations you might not want your eyes to be red. Luckily there are multiple things you can do to get rid of your high eyes:
- As earlier mentioned, we always make sure to have a bottle of eye drops around. It’s not uncommon to have this on you as plenty of people with allergies use this. The eye drops can help to relieve dryness and reduce redness. Most likely this will be the most effective way to get rig of your red eyes fast.
- If you don’t have eye drops around you can also throw some water in your face or put a wet towel on your face for a couple of minutes.
- Some say drinking coffee might help, as caffeine has an opposite effect on the blood vessels in the eyes than weed. Caffeine is a stimulant that causes the blood vessels to contract. This will result in a reduced in flow in your eyes which might help after you’ve hit the bong.
- Last but not least, apply a cold compress. There are many benefits for your eyes with a cold compress as it can relieve symptoms such as swelling, pain, and dryness. The cold rlowers the blood flow in the eyes which helps against the effects of THC and CBD.
How to prevent red eyes after smoking cannabis?
There’s also some things you can do to help prevent instead of avoid the red-eye effect. But be aware, no matter what you do, the more THC and CBD in you consume the bigger the chance your eyes will turn red.
First and most importantly is the dosage of THC. The higher the amount of THC you consume, the more likely you are to get red eyes. Similarly, smoking weed more frequently can increase the likelihood and severity of redness. You could consider to go for a strain with higher CBD content and lower THC content, as this cannabinoid tends to have a weaker response on the blood vessels in your eyes.
Avoid smoking in dry or smoky environments: Dry air can worsen the effects on your eyes, leading to more redness. If possible, smoke in a well-humidified environment or outdoors in humid weather.
Completely avoiding the red eyes is not possible for most people unfortunately. But do all people get red eyes from using marihuana?
Does everybody get red eyes from using marihuana?
Next time when you are hanging out with your friends and smoking weed look around and see if everybody has red eyes. Most likely, they won’t. Not everybody gets red eyes as a side effect, and not every body will get this to the same degree.
The most important factor is the tolerance for THC, the psychoactive compound in weed. The tolerance can heavily change per individual and can be developed when smoking more often and bigger amounts. Therefore, people with a ‘high’ tolerance may not experience the same degree of red eyes, even though they could feel the psychoactive effects of the THC.
The individual health also plays a role in this. For example having a high or low blood pressure can influence if and how red your eyes get.
Is there any harm in getting red eyes?
There is no harm in getting red eyes as a result of smoking cannabis, and in most cases, no treatment is necessary. However, if you are experiencing severe or persistent redness, or if it is accompanied by other symptoms such as pain, vision changes, or discharge, it is important to see a doctor to rule out any underlying medical conditions.
Will eating cannabis help compared to smoking?
No, eating cannabis will not help compared to smoking for the effects on your red eyes. In fact, eating cannabis may actually make your keep your eyes red for a longer period of time. This is because the THC is absorbed into the bloodstream more slowly when it is eaten compared to when it is smoked. This means that the effects of THC, which can contain the red-eye side effect, will take a longer time to appear, but will also last longer.
When you smoke weed, THC is absorbed into the bloodstream immediately. The effects appear almost directly but will also wear off more quickly.
As discussed in this article, a smoky environment can have impact on the redness of your eyes, so in that way this statement is true.
Conclusion
Smoking weed causes red eyes due to the dilation of blood vessels in the eyes. This effect is typically temporary and lasts for 2-4 hours after smoking. However, eating edibles can result in longer-lasting redness, up to 4-8 hours.
The best way to get rid of red eyes is by using eye drops, but avoiding it is not possible when you consume THC.
At Open Your Mind, we believe it is important to provide valuable information to our community. We have many more articles written in our knowledge center around topics of our beloved plant. If you have any ideas for nice subjects for our articles, we are always happy to hear from you!
Disclaimer and source reference
This blog article is for educational purposes only and is not intended to be a substitute for professional medical advice. Please consult with a qualified healthcare professional before making any decisions about your health.
- Yazulla, S. (2008). Endocannabinoids in the retina: From marijuana to Neuroprotection. Progress in Retinal and Eye Research, 27(5), 501–526. https://doi.org/10.1016/j.preteyeres.2008.07.002
- Subramaniam, V. N. (2019, 1 april). The cardiovascular effects of marijuana: Are the potential adverse effects worth the high? PubMed Central (PMC). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6461323/
